I am all for using your hobbies professionally. Indeed, I think the ideal life is one where your hobby and job don't exist – what you'd call "hobbies" and "jobs" are so fused you just have a "life" where the things you like make you money and give you social involvement. To me the holy grail of professional geekdom is like that – a life with no outside (or inside).
A flaw that afflicts some progeeks, and that many don't speak to, is that it's too easy to slide into the idea that just because you're a fannish professional, just because what pays your bills also is the reason you have an extensive action figure collection, that you have to take everything seriously. In short, every "fun" thing has to be calculated to some financial benefit.
I'm here to say that's wrong on two counts.